Crystallization of sugars

ABSTRACT

A process for preparing crystalline sugar by providing a solution of a solvent and sugar, exposing the solution to a magnetic field having a strength which is sufficient to impart improvements in the processing of the sugar or the properties of the resulting crystalline sugar product, and providing conditions suitable for crystallization to obtain a substantially crystalline sugar product. The magnetic field strength is sufficient to influence at least one of morphology, size, nucleation rate or, crystallinity of the crystalline sugar product.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of International ApplicationNo. PCT/EP98/05866 filed Dec. 9, 1998 the content of which is expresslyincorporated herein.

FIELD OF THE INVENTION

The present invention relates to the crystallization of sugars and tosugar crystals obtained thereby.

BACKGROUND ART

Sugars such as sucrose are very widely used, such as in the food andconfectionery industries, and the final stage in the manufacturingprocess of the sugar is often crystallization from an aqueous solutionwith the sugar then being used in crystalline form. Crystallization ofsugars is a complex process which is difficult to control so that thesize and shape of the resulting sugar crystals is often unpredictable.Where crystals of a particular size and shape are required, for examplein certain applications in the confectionery industry, it is difficultto produce crystals in the required form conveniently and consistently.

Sucrose generally crystallizes in anhydrous form although the formationof the hemipentahydrate (C₁₂H₂₂O₁₁.2.5H₂O) and the hemiheptahydrate(C₁₂H₂₂O₁₁.3.5H₂O) has been reported on crystallization at lowtemperature (−34° C.) (Young & Jones, J. Phys.

Colloid Chem., 53, 1334-1350, 1949). The formation of the crystallinehydrates was regarded as a problem in the storage of frozen fruits andinvestigations were undertaken to try to find ways of preventing theirformation (Young et al, Food Research, 16, 20-29 1951).

Engelsen and Pérez (Carbohydrate Res. 292, 21-38, 1996) suggested on thebasis of molecular dynamics simulation (a computer modeling technique)and crystallographic investigation of a sucrose/protein complex thatsucrose may exist in hydrated form in aqueous solution but theseconclusions remain controversial.

Research into the effects of magnetic fields on chemical processes hasbeen sporadic. It was suggested in the 1930s that application of amagnetic field could remove scale from water pipes but in the absence ofa convincing rationale for the effect the technique remainedcontroversial for many years before being confirmed experimentally some50 years later (Donaldson, Tube International, January 1988, 39 andGrimes, Tube International, March 1988, 111). The effect of magneticfields on precipitation and crystallization in inorganic systems such ascalcium carbonate and zinc phosphate is assumed to be on nucleation andcoagulation and the effect in reducing scale formation or even removingscale which has already formed appears to be a result of changes insolubility of the inorganic compound.

In the case of organic molecules, it was found that when benzophenonewas crystallized in a high magnetic field, the direction of the longaxis of the needles formed tended to align perpendicular to thedirection of the magnetic field (Katsuki et al, Chemistry Letters, 1996607-608). With a more complex organic molecule, a considerable degree ofalignment was found when fibrin was allowed to polymerize in a magneticfield and a possible effect on blood clotting in vivo was suggested(Yamagishi et al, J. Phys. Soc. Jpn., 58(7), 2280-2283, 1989). A recentreport has also suggested that application of a magnetic field caninfluence the selectivity ratios in the nickel catalyzed hydrogenationof fats such as sesame oil and soybean oil (Jart, JAOCS, 75(4), 615-617,1997).

Experiments have been reported in which passing sucrose solution througha magnetic field appeared to reduce the boiling point of the solutionalthough a drop in boiling point was also noted for distilled water andtap water. The magnetic field also affected viscosity and surfacetension of the sucrose solution but the various effects were notproportional to the intensity of the magnetic field (Bisheng et al.,Int. Sugar Journal, 98, 73-75, 1996). It has also been suggested thatthe application of a magnetic field can reduce and control evaporatorscale in the production of cane sugar (Cole & Clarke, Int. SugarJournal., 98, 71-72, 1996). There is no suggestion in either of thesepapers of any effect on the sucrose crystals themselves.

The present invention relates to a method by which the crystallizationof sugars can be influenced so that a particular desired crystallineproduct can be formed conveniently and consistently.

SUMMARY OF THE INVENTION

The present invention relates to process for preparing crystallinesugar, the process comprising providing a solution comprising a solventand sugar, exposing the solution to a magnetic field having a strengthwhich is sufficient to impart improvements in the processing of thesugar or the properties of the resulting crystalline sugar product, andproviding conditions suitable for crystallization to obtain asubstantially crystalline sugar product.

The sugar is typically sucrose, glucose, fructose, trehalose, lactose,sorbitol, mannitol, erythritol, or combination thereof. In a preferredembodiment, the sugar consists essentially of sucrose or lactose. Inanother embodiment of the invention, the solvent is water and thecrystalline sugar comprises sucrose hydrate containing more than about1% water by weight. In yet another embodiment of the invention, thesugar consists essentially of lactose and water in a higher amount thanknown in the art.

Preferably, the strength of the magnetic field is sufficient toinfluence at least one of a morphology, size, nucleation rate,crystallinity, or combination thereof of the crystalline sugar product.In a preferred embodiment, the solution is exposed to a magnetic fieldfrom at least one permanent magnet during the exposing step, whichmagnet provides a magnetic field strength of at least about 200 G.Alternatively, the solution is exposed to a magnetic field from at leastone DC electromagnet during the exposing step, which magnet provides amagnetic field strength of at least about 30 G. In another embodiment ofthe invention, the process comprises using at least one pulsed magnet.

In the process according to the invention, at least a portion of thesolution is preferably exposed to the magnetic field while evaporatingan amount of solvent sufficient to the crystallization of the sugar.Thus, at least a portion of the solution is preferably maintained at atemperature of from about 30 to about 70 ° C. while evaporating at leasta portion of the solvent.

Another embodiment of the invention relates to food and confectionaryproducts prepared with the crystalline sugar products disclosed hereinas an ingredient or coating.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are illustrated in the appendeddrawing figures, wherein:

FIG. 1 shows the orientation of the magnetic field referred to under1.1(c) below.

FIG. 2 shows (a) wedge growth and (b) dendritic growth of sucrosecrystals.

FIG. 3 is a diagram from above representing sucrose crystal growth underthe conditions of a permanent magnetic field placed above and below thesample.

FIG. 4 is a diagram of pulsed magnet and sucrose solution apparatus.

FIG. 5 shows general euhedral sucrose crystal shapes obtained from DCfield case (iii) below.

FIG. 6 shows surface texture of crystallized sucrose with no magneticfield viewed using SEM at ×540 magnification.

FIG. 7 shows microcrystalline material on the surface of a sucrosecrystal, crystallized in a 700 G permanent magnetic field viewed usingSEM at ×470 magnification.

FIG. 8 shows flat surfaces of a sucrose crystal grown in an 80 Gpermanent magnetic field and viewed using SEM at ×65 magnification.

FIG. 9 shows layered crystal growth viewed on a sucrose crystal surfacegrown in a 700 G permanent magnetic field viewed using SEM at ×170magnification.

FIG. 10 shows the surface of a sucrose crystal grown with no magneticfield viewed using PLM at 10× magnification.

FIG. 11 shows microcrystalline material present on the surface ofsucrose crystals formed in a 300 G DC electromagnetic field.

FIG. 12 shows microcrystalline material present on the surface ofsucrose crystals formed in a 150 G permanent magnetic field.

FIG. 13 shows flat surfaces and angled comers shown on sucrose crystalsgrown in a 400 G DC electromagnetic field.

FIG. 14 shows flat surfaces and angled comers shown on sucrose crystalsgrown in a 400 G DC electromagnetic field.

FIG. 15 shows layered growth of sucrose crystal surfaces grown in a 150G permanent magnetic field.

FIG. 16 shows layered growth of sucrose crystal surfaces grown in a 350G DC electromagnetic field.

FIG. 17 shows the DSC melting profile for sucrose control (“no-field”)crystals.

FIG. 18 shows DSC melting profile for sucrose crystals grown in a 300 Gpermanent magnetic field.

FIG. 19 shows DSC melting profile for sucrose crystals grown in a 600 Gpermanent magnetic field.

FIG. 20 shows a diagrammatic illustration of an apparatus forcrystallization of lactose under a permanent magnetic field at sides inparallel.

FIG. 21 shows a diagrammatic illustration of an apparatus forcrystallization of lactose under a permanent magnetic field above andbelow.

FIG. 22 shows a diagrammatic illustration of an apparatus forcrystallization of lactose under a pulsed magnetic field.

FIG. 23 shows a diagrammatic illustration of an apparatus forcrystallization of lactose under a DC electromagnetic field.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Herein, the term “sugar” is used generally to refer, for example, to anymonosaccharide, disaccharide, oligo-saccharide, sugar alcohol, orcombination thereof that will combine to form a substantiallycrystalline sugar product. Polyols obtained by reduction of thecorresponding sugar may also be used. In one embodiment of theinvention, the sugar comprises any substantially water solublemonosaccharide, disaccharide, oligo-saccharide, sugar alcohol, orcombination thereof. For example, sugars such as sucrose, glucose,fructose, trehalose, lactose, sorbitol, mannitol, erythritol, orcombination thereof may be used. In one embodiment, the sugar consistsessentially of lactose. In a preferred embodiment, the sugar consistsessentially of sucrose, and the solvent is water.

The solvent may comprise any solvent or mixture of solvents so long asan amount of sugar sufficient to allow for crystallization is solubletherein when the solvent is at a desired temperature. The process of thepresent invention may be used with sugar syrups that are known in art.In a preferred embodiment, the solvent is water. In a more preferredembodiment the solvent comprises deionized water.

The solvent may also be a solution of water and at least one alcohol.Alternatively, the solvent may be an organic solution of an alcohol or amixture of two or more alcohols.

The sugar solution is preferably undersaturated. In a preferredembodiment the sugar solution is between about 1 and 35% undersaturated,i.e., between about 99 and 65% saturated. In a more preferredembodiment, the solution is between about 10 to 30%, and more preferablyabout 20%, undersaturated, i.e., between about 90 to 70%, and morepreferably about 80% saturated. However, the present invention may alsobe used with solutions that are provided saturated or that becomesaturated during crystallization, provided that seed crystals are notpresent when the magnetic field is applied. Or, the temperature may beraised or lowered during crystallization to, for example, increase ordecrease a rate of solvent evaporation.

It is understood in the art that the degree of saturation depends on,among other parameters, the temperature of the solution and the sugar.For example, in one embodiment of the invention, the temperature of thesolution during at least a portion of the process is from about 30 toabout 70° C. and the solution comprises from about 20 to about 95% sugarand about 80 to about 5% water based on the total weight of thesolution. In a still more preferred embodiment, the temperature of thesolution is from about 30 to about 70° C. during at least a portion ofthe crystallization and the solution comprises from about 20 to 75% andpreferably 20 to 40% sucrose and about 80 to 25%, and preferably 80 to60% water based on the total weight of the solution. In a most preferredembodiment, the temperature of the solution is about 50° C. during atleast a portion of the crystallization and the solution comprises about33% sucrose and about 67% water based on the total weight of thesolution.

It is understood in the art that crystallization comprises complexprocesses leading to the growth and recovery of crystals from a solutioncomprising molecules suitable for crystal growth. Crystallizationcomprises, but is not limited to, processes such as, nucleation, crystalgrowth, attrition, agglomeration, and maturation of crystals.Crystallization is usually initiated by evaporating at least a portionof the solvent. However, other methods such as agitation or seeding, asare understood in the art, can be used alone or in combination withevaporation in the process of the present invention. Oncecrystallization has proceeded for a desired length of time or whensubstantially all or most of the solvent has evaporated, the crystallinesugar of the present invention can be recovered and dried by methodsknown in the art. Preferably, the recovered, dried crystals haveproperties desirably associated with sugar such, for example, as apredetermined pourability, morphology, or crystallinity, as can bedetermined using methods known in the art.

In general, crystallization is induced by allowing at least a portion ofthe solvent to evaporate. In a preferred embodiment, a sufficient amountof solvent evaporates to allow recovery of sugar having desiredproperties such as, for example, pourability and crystallinity. In amore preferred embodiment substantially all of the solvent evaporatesduring crystallization. Recovery of crystalline sugar may furthercomprise such steps as, for example, drying which are understood.

During crystallization, fans or other devices may be used to circulateair or other gas above the solution to urge evaporation of the solvent.Also, the relative humidity of the air or other gas, such as solventvapor, in contact with the solution may be varied to adjust the rate ofevaporation and/or crystallization. During crystallization, the relativehumidity of the gas contacting the solution is preferably less thanabout 100%, more preferably less than about 75%.

During at least a portion of crystallization, the temperature of atleast a portion of the solution is preferably from about 10 to 100° C.,although the crystallization can be carried out at from about the lowesttemperature at which the solvent evaporates up to the boiling point. Ina preferred embodiment, during at least a portion of thecrystallization, the temperature of at least a portion of the solutionis preferably about 30 to 70° C.; for example, most preferably, forexample, about 50° C.

In one embodiment of the invention, at least a portion of the solutionis maintained at substantially the same temperature during substantiallyall of the crystallization step. In another embodiment, the temperatureof at least a portion of the solution may be sequentially decreased ascrystallization proceeds. Such temperature variations allow the rate ofevaporation and/or crystallization to be adjusted as needed. It is alsopossible to vary the pressure of the air or other gas contacting thesolution to adjust the solvent boiling point to a predeterminedtemperature.

Seed crystals may be added to the solution. In a preferred embodiment,the seed crystals represent, at least in part, a crystalline productobtained by the presently recited process and recycled in a subsequentcrystallization process.

Crystalline sugar obtainable by the present process preferably comprisesat least one hydrated form of the sugar, crystalline other hydrates,hydrate or combination thereof. A portion of the crystalline sugarprepared according to the invention may comprise anhydrous sugar,however, the present method advantageously allows the preparation ofcrystalline sugar comprising a larger amount of water than sugarprepared by methods known in the art. Herein, the terms hydrated form,hydrate, or crystalline hydrate mean sugar comprising extra water whichmay be tightly bound but is detectable by, for example, Karl Fischertitration or differential scanning calorimetry (DSC). Thus, for example,the hydrated form, hydrate, or crystalline hydrate of sugar obtainableby the process of the invention may preferably comprise water moleculesincorporated into the sugar crystal lattice and are tightly held withinthe molecular structure of the sugar. For example, the hydrate of theinvention may preferably be distinguished using DSC from sugarconsisting substantially of anhydrous sugar or sugar prepared withoutexposure to a sufficiently strong magnetic field. Additionally, waterinclusions or surface water may be present. In a preferred embodiment,the sugar prepared by the process of the invention comprises sucrosehydrate and further comprises at least about 1% water by weight, andmore preferably at least about 10% water by weight.

The sucrose hydrate prepared by the process of the invention, preferablycomprises sucrose hemi-pentahydrate, sucrose hemi-heptahydrate, or acombination thereof. The sucrose hydrate preferably exhibits a peak atabout 150° C. using DSC. In a more preferred embodiment the ratio of thepeak at about 150° C. to a peak at about 180° C. is at least about 0.3.

In one embodiment, the sugar comprising sucrose hydrate is crystallizedfrom an aqueous solution having a temperature of at least about 0° C.about to the boiling point of the solution during at least a portion ofthe crystallization; for example, preferably the solution has atemperature of from about 30 to 60° C., most preferred the temperatureis about 50° C.

In another embodiment, the sugar obtained by the process of the presentinvention comprises α-lactose hydrate. In a preferred embodiment thecrystalline sugar comprising α-lactose hydrate further comprises atleast about 7% water by weight. In a still more preferred embodiment,the crystal comprising α-lactose hydrate further comprises at leastabout 9% water by weight.

According to the invention, the solution is exposed to a magnetic fieldhaving strength sufficient to influence at least one of a morphology,size, nucleation rate, crystallinity, or combination thereof of thecrystalline sugar. In particular, the size and/or shape of the crystalsproduced according to the invention can be influenced as desired. Oncethe particular type and orientation of magnetic field and the manner ofits application which leads to crystals with the desired properties(size, shape, etc.,) has been determined, then application of that fieldenables the desired crystals to be produced subsequently with a highdegree of consistency.

In yet another embodiment of the invention, crystalline sucrose obtainedby the process of the invention comprises crystals at least about 100μm, for example, preferably at least about 500 μm, and, most preferably,at least about 1000 μm. In another embodiment of the present invention,the sugar crystals are preferably substantially microcrystalline, forexample, smaller than about 40 μm or, more preferably, smaller thanabout 25 μm. In a preferred embodiment of any of the above crystals, thecrystals are substantially rectangular or wedge shaped.

Preferably, the solution is exposed to a magnetic field that is strongerthan the magnetic field of the earth, which is about 0.5 Gauss (“G”).The upper limit is not critical but the invention is operable atrelatively low levels of up to 1000 G. Thus a magnetic field of at least1 G, preferably at least 10 and more preferably at least 25 G is used.Any type of magnet or combination of magnets can be used to apply thismagnetic field. For example, the magnets may include permanent magnets,electromagnets such as, for example, pulsed electromagnets and DCelectromagnets, or combination thereof. A pulsed or alternating magnetis a magnet capable of applying a magnetic field that varies in time.Radio frequency generated magnetic fields may used alone or incombination with any of the permanent or electromagnets above. Themagnetic field may comprise a single magnetic field or a superpositionof magnetic fields. The superposition of magnetic fields may comprise aconstant and an alternating magnetic field. The present invention doesnot require that the magnetic field have a substantially homogenousstrength throughout the entire solution.

The effect of different types of magnetic fields is discussed in moredetail in the experimental work described below. However, in generalterms, DC electromagnetic fields promote euhedral growth (morerectangular crystal form) and also slow the crystal growth whereas thenumber of centers of growth (nucleation) increases with increasing fieldstrength. Thus, for example, a DC electromagnetic field may preferablybe used to obtain a large quantity of regular crystals with a fineparticle size, because preparation of such crystals requires a processwhich promotes nucleation more than crystal growth. In general,permanent magnetic fields reduce the number of centers of growth withincreasing field strength.

In an embodiment of the invention, at least a portion of the solution isexposed to a magnetic field from at least one permanent magnet, whichprovides a magnetic field strength of at least about 50 G, preferably atleast about 200 G, and more preferably at least about 450 G, and mostpreferably at least about 600 G. In a preferred embodiment, at least aportion of the solution is disposed between at least a portion of twosubstantially opposed electromagnets during the applying magnetic fieldstep. However, the magnets may also be arranged in any geometry so as toexpose at least a portion of the solution to a superposition of magneticfields.

At least one DC electromagnet may be used to apply a magnetic field tothe solution. In a preferred embodiment at least two DC electromagnetsare disposed on at least two opposed sides of at least a portion of thesolution. The magnetic field applied by the DC electromagnets is atleast about 30 G in at least a portion of the solution, preferably atleast about 150 G, more preferably at least about 400 G. The nucleationexposure of the solution to a DC electromagnetic field increases thenucleation rate by a factor at least about 1.5 compared to a solutionthat has not been exposed to an applied magnetic field.

In the laboratory scale work described below, crystallization is carriedout in Petri dishes. The present process, however, can advantageously becarried out on a commercial scale using any crystallization apparatus,as understood in the sugar industry.

Seed crystals may also be employed in the process of the presentinvention. The seed crystals employed in the process may be derived fromany source, but typically should be of the same general type, characterand nature of that of the composition of the sugar in the solutioncomposition, since variations in the nature of the seed crystals fromthat of the solution composition affect the crystalline properties andcrystallization time. If used, it is preferred that the seed crystalsrepresent, at least in part, a crystalline product obtained in thepresently recited process and recycled in a subsequent crystallizationprocess.

The magnetic field is generally applied to at least a portion of thesolution prior to crystallization or evaporation of a sufficient amountof solvent to induce crystallization. Indeed, the magnetic field may beapplied to the solution hours or even days prior to crystallization.Preferably, the magnetic field is applied to at least a portion of thesolution within about 1 hour prior to inducing crystallization.

If desired, the magnetic field may be applied to at least a portion ofthe solution during at least a portion of crystallization and solventevaporation. The magnetic field may be applied to the solution duringsubstantially all of the crystallization and evaporation. In addition,any combination of magnetic fields applied both prior to and duringcrystallization and evaporation may be used for certain situations.

The magnetic field is typically applied to the solution in the samelocation as crystallization or evaporation. Alternatively, the magneticfield may be applied to the solution in a different location fromcrystallization or evaporation. In a preferred embodiment, flow is usedto transport the solution from the magnetic field to a differentlocation for crystallization and evaporation. In addition, at least aportion of the solution may be exposed to the magnetic field more thanonce, as, for example, by flowing the solution at least twice through amagnetic field.

The fact that the present invention enables sugars to be produced in adesired crystal size and/or shape more conveniently and consistentlywill be of benefit, for example, in most applications of the sugar inquestion where the sugar is to be used in solid form rather than beingdissolved. Preferably, the hydrates of the invention possess desirableproperties relating to, for example, pourability and crystallinity.Thus, another aspect of the invention relates to a confectionarycomposition comprising a hydrate of a crystalline sugar obtainable bythe process according to the invention. In a preferred embodiment, theconfectionary composition comprises sucrose hydrate, α-lactose hydrate,erythritol, or a combination thereof. In a more preferred embodiment,the confectionary composition comprises a sucrose hydrate obtainable bythe process according to the invention and comprising at least about 1%water by weight, more preferably at least about 10% water by weight.

In particular, any of the above confectionary compositions may be acoating. For example, and not by way of limitation, in the production ofconfectionary coatings for food products, such as chocolate buttons suchas the product sold under the trade mark SMARTIES®, it is oftenimportant that the coating should have an attractive bright and shinyappearance. This appearance, which depends at least in part on theparticle size of the sugar, can be controlled by use of microcrystallinesugar which can be produced conveniently and consistently by the processaccording to the invention.

In other confectionery applications, such as, for example, theproduction of fruit pastilles, large crystals of sucrose (100 μm up to 2or 3 mm) are required for coating the pastilles because of theirparticular properties of texture and light reflectance. Such crystalscan again be produced conveniently and consistently by the processaccording to the invention. Sucrose crystals of particular shapes can beproduced according to the invention to obtain specific desired effects.

The fact that the sucrose can be produced in the form of a crystallinehydrate may be an advantage in other areas of the confectionery industrysuch as, for example, the manufacture of milk chocolate, which involvesthe formation of so-called crumb, which is a mixture of dried milk,sucrose and cocoa butter. Amorphous sucrose is formed during some crumbmaking processes and traps fat leading to an increase in the amount offat which is required in the final chocolate recipe. Milk fat is one ofthe most expensive ingredient in milk chocolate and the use ofcrystalline sucrose which does not trap fat means that the amount ofthis expensive ingredient can be reduced. Reducing the amount of fat inthe chocolate would also have the effect of reducing the calorificvalue.

In addition, sucrose represents about half of the total weight of milkchocolate. Thus, use of a crystalline sucrose hydrate having added waterwill further reduce the caloric value of the chocolate. A preferredembodiment of the invention, comprises a chocolate confection comprisingsucrose and further comprising sucrose hydrate wherein the sucrose has awater content sufficient to reduce the caloric value of the chocolate.Preferably, the sucrose comprises at least about 1% water by weight, andmore preferably at least about 10% water by weight. Accordingly, use ofcrystalline sucrose produced according to the present invention allows asignificant reduction to be made in the calorific value of the chocolatewithout any adverse effects on the taste and other properties thereofthe chocolate. Another aspect of the present invention relates to achocolate confectionary composition comprising chocolate and acrystalline sugar obtainable by the process according to the invention.

In a preferred embodiment the chocolate confectionary compositioncomprises sucrose hydrate, lactose hydrate, erythritol, or anycombination thereof. In one embodiment, the chocolate confectioncomprises a sufficient amount of crystalline erythritol obtainable bythe process of the invention to reduce advantageously the caloriccontent of the chocolate confection. In a more preferred embodiment, thechocolate confectionary composition is prepared with sugar comprising alactose hydrate obtainable by the process of the invention and issubstantially free of added sucrose.

In another embodiment, the chocolate confectionary composition isprepared with crystalline sugar obtainable by the process of theinvention and comprises at least about 5% fewer calories than achocolate confectionary composition prepared with substantiallyanhydrous sugar and having similar organoleptic qualities. In a mostpreferred embodiment, the chocolate confectionary composition isprepared with substantially crystalline sucrose which comprisessufficient amount of sucrose hydrate to reduce the amount of calories byat least about 5% as compared to a chocolate confectionary compositionprepared with substantially anhydrous sucrose and having similarorganoleptic qualities.

Another embodiment of the present invention relates to a food productprepared with a crystalline sugar obtainable by the process of thepresent invention. Preferably, the food product comprises a crystallinesucrose hydrate comprising at least about 1% water by weight, morepreferably at least about 10% water by weight. The crystalline sucrosehydrate may be in combination with anhydrous sucrose. Yet anotherpreferred embodiment relates to a food product prepared with acrystalline lactose obtainable by the process of the present invention,more preferably the food product is substantially free of sucrose inamount sufficient to alter the calorie or organoleptic properties of thefood.

The use of techniques such as differential scanning calorimetry (DSC),scanning electron microscopy (SEM), polarizing light microscopy (PLM)and powder X-ray diffraction (XRD) has shown that in the case of sucrosethe properties of the crystals formed are consistent with a significantproportion being sucrose hydrates, probably mixtures of thehemi-pentahydrate and the hemi-heptahydrate, in admixture with someanhydrous sucrose. Given that the literature discloses these hydrates asbeing formed only at low temperatures, it is surprising that they can beformed according to the invention at ordinary or elevated temperatures.

EXAMPLES

The invention is illustrated and supported further by the followingexperimental work, which is presented by way of example only.

1. Static Crystallization of Sucrose

1.1.0 Experimental

1.1.1 Preliminary Studies

Saturated solutions of sucrose were prepared in 5 cm Petri dishes on ahot plate at 50° C. by addition of sucrose to an unspecified amount ofde-ionized water until no more sucrose could be dissolved. In the casesof over-addition of sucrose, more water was added to water down thesolution. The sucrose solutions in the Petri-dishes, placed inincubators at 50° C., were left to evaporate and crystallize under thedifferent magnetic environments (a)-(f) listed below.

(a) No magnetic field around the crystallizing sucrose solution.

(b) Permanent magnets placed either side of the Petri-dish with fieldstrengths of:

(i) 300 G at edges, 265 G at center of Petri-dish

(ii) 400 G at edges, 350 G at center of Petri-dish

(iii) 640 G at edges, 540 G at center of Petri-dish

(iv) 760 G at edges, 630 G at center of Petri-dish.

(c) Permanent magnets 1 placed in a square around a Petri dish 2, asshown in FIG. 1. The field strength at a point 3 was 260 G, at a point 4was 200 G, at a point 5 was 60 G, and at a point 6 was 50 G.

(d) Permanent magnets placed above and below Petri-dish with a fieldstrength of 60 G.

(e) A pulsed magnetic field that passes in two directions alternatelywith the Petri-dish placed above the center.

(f) DC electromagnets with poles placed at either side of the Petri-dishwith field strengths of:

(i) 100 G at edges, 50 G at center of Petri-dish

(ii) 320 G at edges, 140 G at center of Petri-dish

(iii) 500 G at edges, 195 G at center of Petri-dish

(iv) 600 G at edges, 220 G at center of Petri-dish.

Visual observations were recorded following crystallization of thesucrose solutions and the crystals collected and dried.

1.1.2 Controlled Conditions Investigation

Experiments were performed under the same format as before but withalterations listed below included in the preparation of samples beforeplacement in incubators:

(a) 10 ml de-ionized water was placed in the Petri-dishes,

(b) 4.66 g sucrose was added to the water (around 80% saturated) andheated on a hot-plate at 50° C. for two hours until fully dissolved,

(c) Samples were prepared free of dust or foreign material by coveringthe Petri-dishes during the sucrose dissolving stage.

Each experiment was repeated 3 times and visual observations were noted.

1.2.0 Results and Discussion

1.2.1 Results from preliminary studies on static sucrose crystal growth

The main aim of the experiment was to create a controlled environmentwhich would allow evaporation of water from aqueous sucrose solutions,i.e. slow crystallization of sucrose, and to investigate the effect onthe crystal growth process of various magnetic fields.

Five centimeter diameter Petri-dishes were utilized as a crystal growthcontainer as its size allowed evaporation and crystal growth over thecourse of 2 days. The solutions for the preliminary trials were preparedin the Petri-dishes in an unmeasured amount of de-ionized water.Incubators were used as a means of controlling the temperature andincluded a fan that circulated the air inside to aid evaporation.

Evaporation studies showed that over-saturation resulted in catastrophicsolidification in the form of small rectangular crystals that formed afilm across the solution/air interface within 2 hours. In general, lowerlevels of saturation resulted in crystal growth in a characteristiccircular fan pattern. Growth begins from a point of nucleation 7 andcontinues circularly outwards forming single crystal wedges with largercrystal growth faces (see FIG. 2(a)). In some cases finer, needle-likecrystals can be formed which will be referred to as dendritic and wherethe needles do not originate from the point of nucleation 7 but from apoint of growth at some distance from the center (see FIG. 2(b)). Sincedifferent forms were obtained from different levels of saturation theinvestigation was continued under controlled conditions.

1.2.2 Visual Observations From Controlled Studies

1.2.2(a) Control or “No Field” Sucrose Crystals

Sucrose crystals grown without a magnetic field in general formed over24 hours. The earliest centers of nucleation resulted in the largestcircular diameters of growth that predominated most of the surface ofthe sucrose solution. On average there were five centers of nucleationwith 3 larger that predominated the sucrose solution surface. Thesmaller crystal growths which will be referred to as secondarynucleations, formed in the remaining solution around the larger areas ofcrystal growth until there was no sucrose solution/air interface left.The crystal surfaces were in general, uneven, disordered and chunky,especially where the crystallization from different centers ofnucleation met, and were in the form of wedge growth.

30 1.2.2(b) Permanent Magnetic Fields

The general forms of the sucrose crystals obtained from the permanentmagnetic field studies were similar to the “no-field” situation i.e.circular growth patterns, but there were subtle differences worthnoting.

1.2.2(b) (i) 300 G at Edges, 265 G at Center of Petri-dish

Here, the weakest permanent field had a similar number of centers ofnucleation i.e. on average around 6 or 7. The largest circular growthpatterns came from three nucleation centers and there were on average 3to 4 smaller growth patterns from secondary nucleations. The mostobvious visual difference was the fine structure that made up thecircular growth patterns. The crystals were very clear in appearancemade up of many fine wedges that have grown in very straight linesoutwards from the point of nucleation. Boundaries of the circular growthpatterns formed almost straight lines and there were no chunky ordisorganized regions. In general, the crystal growths were more orderedand had a finer structure.

1.2.2(b)(ii) 400 G at Edges, 350 G at Center of Petri-dish

On average, use of a slightly stronger permanent field resulted in fewercenters of nucleation i.e. on average 5. In most cases, the majority ofsucrose crystal growth came from 4 centers of nucleation that dominatedthe surface of the sucrose solution. In addition to the finer structureof the sucrose crystal growth observed in the weaker permanent fieldcase, some flat clear wedges were observed.

Boundaries between circular growth patterns were again almost straightlines and in general the sucrose crystals grown under these magneticconditions were more ordered than the “no-field” situation.

1.2.2(b)(iii) 640 G at Edges, 540 G at Center of Petri-dish

Fewer centers of nucleation (on average 4) were observed from thesucrose crystal growth under stronger permanent magnetic fieldconditions. However, since there were no secondary nucleation centers,crystal growth came from around four centers of nucleation resulting inlarger diameters of growth. The sucrose crystal growth was fine at thecenters of nucleation, but became wider, flat, clear wedges as growthcontinued away from the center. Incomplete layered crystal growth couldbe seen on the flat, wedge surfaces and caused them to look opaque.Boundaries were again very even and the growth patterns more orderedthan the “no-field” conditions.

1.2.2(b) (iv) 760 G at Edges, 630 G at Center of Petri-dish

Again fewer centers of nucleation (on average 2) were observed from thestronger permanent field sucrose crystal growth conditions. Wherecrystal growth was close to the center of nucleation, the sucrosecrystals were fine but dendritic. Some had the appearance of overlappingwedges. Growth away from the center of nucleation resulted in large wellformed wedges with layered growth visible. Boundaries of circulargrowths were in the form of interlocking zigzags indicating crystaltwinning and were even and flat. Secondary nucleation was limited to avery small area and on average consisted of growth from only 1 or 2centers. The resulting secondary nucleation sucrose crystals wereordered and fine. In summary, the growth patterns resulted in veryordered, and excessively large wedges in most cases with some evidenceof dendritic growth.

1.2.2(c) Permanent Magnetic Fields in a Square Around Sample

The square orientation of the permanent magnets resulted in crystalswith more needle shape. Growth was dendritic therefore wedge shapes werenot observed. On average there were two larger spherulitic growths and 3or 4 smaller ones. As the diameter of the spherulitic growth becamelarger more needles began to grow, and most had the dimensions of 2-3 mmwidth with variable length. Boundaries between spherulitic growths arelike interlinking zigzags (twinning) and are well ordered and flat. Theoverall impression is that it is more ordered crystal growth than the“no-field” situation as crystals are clear and well formed.

1.2.2(d) Permanent Magnetic Field Above and Below Sample

Crystal growth was again fine and ordered in appearance consistingmainly of fine wedges or needles. In addition, there appeared to be afavored direction of growth for larger wedges 8 as shown in FIG. 3,which is a diagram from above representing sucrose crystal growth underthe conditions of a permanent magnetic field placed above and below thesample.

In addition, the numbers of centers of nucleation was on average 3, areduction from the “no-field” case. In some cases, secondary nucleationwas observed but was limited to very small growth areas. The boundariesof the circular growths had the appearance of interconnecting zigzags(twinning) and was ordered in appearance. The fine, almost needle-likewedges were very clear, however the larger wedges were opaque from theincomplete layers of crystal growth. In summary, the sucrose crystalsgrown under these conditions appeared to result in a more orderedcrystal but demonstrated a favored direction of growth.

1.2.2(e) Pulsed Magnetic Field

The pulsed magnet 9 is incorporated into a rectangular plastic deviceshown in FIG. 4. The 5 cm Petri-dish 2 was placed on top of the magneticunit as it was too large to fit in the square hole as normally used.Primary nucleation on several occasions occurred predominantly on aright hand side 10 of the Petri-dish but growth on this side was slow.Secondary nucleation on a left hand side 11 and was followed withincreased growth rate. Most of the resulting sucrose crystallizationcame from the left hand side from on average 3 or 4 centers ofnucleation in large circular wedge fans. These were more ordered inappearance than the “no-field” situation and showed sharper edges. Theright hand side had on average 4 or 5 very small, fine circular wedgegrowths.

This result was not always reproducible and so the experiment wasrepeated several times more. On one occasion there was no nucleation onthe right hand side, only large wedged growth from centers of nucleationon the left hand side. Two other experiments showed a selection ofsmaller circular growth patterns, on average 10, occurring with finedendritic growth.

1.2.2(f) DC Electromagnetic Fields

The general forms of the sucrose crystals obtained from the DCelectromagnetic field studies were altered in the stronger field casesfrom the “no-field” situation with in general euhydral growthpredominating.

1.2.2(f) (i) 100 G at Edges, 50 G at Center of Petri-dish

The sucrose crystals under DC electromagnetic field conditions had onaverage 3 large circular growths that predominated most of the surfaceof the sucrose solution. These fine wedge growths showed a small amountof dendricity and were very ordered in appearance. There were inaddition around 3 or 4 smaller circular growths that were finer but lesswell ordered with some disorganized areas. Boundaries of the circulargrowths were interlocking zigzags and were ordered. In summary, thesucrose crystals were fine and more ordered than the “no-field”situation.

1.2.2(f) (ii) 320 G at Edges, 140 G at Center of Petri-dish

More large centers of nucleation (on average 5) were observed underthese conditions of sucrose crystal growth, with around 3 or 4 smallercircular growths. In general, there is more dendricity, and moreirregular patterns within the expected circular growth patterns. Layeredgrowth can be seen very clearly from most of the wedges and crystals arepredominantly more needle shaped from the increased dendricity. Insummary, nucleation has increased but growth is more irregular than inthe weaker field case, although crystals are more ordered than the“no-field” case.

5 1.2.2(f) (iii) 500 G at Edges, 195 G at Center of Petri-dish

The stronger DC electromagnetic field resulted in more centers ofnucleation (on average 6) with 3 or 4 smaller growths, but the mainpoint of note was the shape of the crystals that were obtained. Thecenters of nucleation were not points as in all previous cases but wererectangular crystals. Growth from these rectangular nucleation pointswas rectangular 12 with definite flat edges 13 as shown in FIG. 5 and isnormally termed euhydral. Crystals were more chunky in appearance andcrystallinity appeared improved. Ends 14 of the growth rectangles weresquare in shape and borders between circular growths were straightindicating no crystal twinning has occurred. In addition, the crystalgrowth time was slower taking around twice as long to crystallize overthe sucrose solution surface/air interface. In summary, the DC magneticfield appears to have altered the sucrose morphology, growth rate andcrystallinity.

1.2.2(f)(iv) 600 G at Edges, 220 G at Center of Petri-dish

The effects from the last DC electromagnetic field were emphasized underthese stronger conditions. Around 10 or 11 centers of nucleation wereobserved in most cases, with euhydral growth predominant. In addition,the growth rate appeared to be even slower than case (f) (iii), takingaround 3 days to crystallize over the sucrose solution surface. Insummary, an increased DC electromagnetic field has reduced, the growthrate, increased the nucleation rate, changed the morphology andincreased the crystallinity.

Results are summarized in the following Table:

TABLE 1.2 TYPE OF NO. OF NO. OF TOTAL FIELD AND NUCLEATION NUCLEATIONNUCLEATION GEOMETRY STRENGTH CENTERS CENTERS CENTERS N/A Control 3 2 5Parallel Permanent 3 3 to 4 6 or 7 N-S (265-300G) Parallel Permanent 4 15 N-S (350-400G) Parallel Permanent 4 0 4 N-S (540-640G) ParallelPermanent 1 1 2 N-S (630-760G) Square Permanent 2 3 or 4 5 or 6 (FIG. 1)(60-260G) Above and Permanent 3 0 3 below N-S (60G) N/A Pulsed 3 or 4 4or 5 7 to 9 N-S DC 3 3 or 4 6 or 7 electro magnetic (50-100 G) N-S DC 53 or 4 8 or 9 electro magnetic (140-320G) N-S DC 6 3 or 4 9 OR 10electro magnetic (195-500 G) N-S DC 10 OR 11 0 10 OR 11 electro magnetic(220-600 G)

1.3.0 Conclusion

These preliminary results suggest that static sucrose crystal growth canbe affected by external magnetic fields. Magnetic fields appear to havealtered crystal characteristics such as growth rate, nucleation rate,morphology and crystallinity.

1.4.0 Further Investigations of Static Crystallization of Sucrose inMagnetic Fields

Differential Scanning Calorimetry (DSC) was carried out using a PerkinElmer DCS7. Powder X-Ray Diffraction (XRD) was carried out using aPhilips PW 1710 diffractometer with Cu K_(α) radiation. ScanningElectron Microscopy (SEM) was carried out using a Cambridge 5250stereoscan. Karl Fischer titrations (KF) were carried out using an OrionResearch Inc. Turbo 2 Titrator.

Scanning Electron Microscopy (SEM) was used to look at the smaller=structure of sucrose crystals produced as described above at around ×50to ×500 magnification. Here also, some very large differences in surfacetexture could be seen.

The control samples (“no-field”) showed a very irregular surface texturemade up of blobs of sucrose on the surface. These were poorlycrystallized lumps and the surface was almost amorphous in texture (seeFIG. 6).

By comparison, all samples of sucrose that were crystallized in amagnetic field showed a large amount of micro crystalline material (seeFIG. 7). As seen in FIG. 7, many of the crystals were smaller than about25 μm on edge. These crystals are well formed and angular with very flatsurfaces. In addition, the larger crystals had very flat, smoothsurfaces with definite angled faces of growth as demonstrated in FIG. 8.These surfaces also showed very definite layered crystal growth whichappear to the naked eye as opaque (or cloudy) surfaces (see FIG. 9).

Polarizing Light Microscopy (PLN) at ×10 magnification showed similarfeatures on the sucrose crystals. The control (“no-field”) samples hadlumpy, irregular surfaces shown in FIG. 10, while the samplescrystallized in magnetic fields showed a large amount ofmicro-crystalline material present shown in FIGS. 11 and 12. Flatregular surfaces are shown in FIGS. 13 and 14 and again layered growthin FIGS. 15 and 16.

Differential Scanning Calorimetry (DSC) gives the melting profile of thesucrose crystals. Normally sucrose crystals are anhydrous (i.e. devoidof water) and melt around as indicated by a peak 15 at 180-192° C. in aDSC trace for anhydrous sucrose, which is shown in FIG. 17. There areliterature reports (referred to above) of the formation of hydratedsucrose but the product has been formed exclusively at −30 to 0° C.

In every case of sucrose crystallization within a magnetic fieldreported herein, two or three other features appear on DSC with a peak16 related to a second melting point around 150° C. and in some cases athird melting phase around 170° C. in addition to the normal sucrosemelting peak at 180-192° C. These are shown in FIGS. 18 and 19. Twopossible explanations for the presence of additional peaks on DSC couldbe (1) formation of sucrose hydrates, or (2) a new crystalline sucrosephase.

The % moisture content (by weight ratio) of the sucrose crystals wasmeasured using Carl Fischer titrations. Bottled crystalline sucrose hada moisture content of around 0.02%, while the control (i.e. no magneticfield) samples had a moisture content of around 0.06%. The mostsignificant change in moisture content was for a sucrose crystal grownin a permanent magnetic field (field strength of around 380 Gauss) thatwas a 15 fold increase in water inclusion within the sucrose crystal togive a moisture content of around 1%.

There are three possible explanations for the additional water inclusion(1) surface water that is weakly bound to the sucrose crystal surface,(2) “packets” of trapped water (water inclusions) within the unevenpacking of the crystal that would again be weakly bound to the sucrosecrystal, or (3) water molecules have been incorporated into the sucrosecrystal lattice and are very tightly held within the sucrose molecularstructure.

To eliminate the possibilities of both (1) and (2), ground sucrosecrystals produced according to the invention were dried over phosphoruspentoxide for 40 hours to allow for removal of any weakly bound water.The resulting DSC trace of the dried sucrose crystal showed meltingpeaks at 150° C. and 180° C. suggesting that removal of the weakly boundwater did not alter the melting profile of the sucrose crystal.

In order to identify the nature of this water, solid state proton NMRwas carried out on the sample. Immediate data collection followingcrushing of the sample revealed a broad peak indicative of weakly boundwater from inclusion water, i.e. sucrose syrup at around 5.5 ppm. Asample ground several days before would be expected to be devoid ofwater inclusions but showed a sharper peak at around 5.5 ppm. This isindicative of bound water within the sucrose crystal.

Therefore, the results of the moisture content investigations providesupport for a novel sucrose hydrate production at 50° C.

Powder X-ray diffraction (XRD) of sucrose crystals produced according tothe invention, revealed a complex diffraction pattern when compared toliterature powder XRD data recorded for sucrose hemi-pentahydrate andsucrose hemi-heptahydrate. The diffraction patterns when compared tothat of standard sucrose showed many broader peaks that were off-center,with d-spacings both greater and smaller than the standard sucrosevalues, and were of greater intensity. The diffraction patterns of thesamples were consistent with the presence of a mixture of the twohydrates and anhydrous sucrose. In conclusion therefore, it is mostlikely that sucrose hydrates have been prepared by the application ofmagnetic fields around the crystallizing samples.

2. Dynamic Investigations into Sucrose crystallizations using MagneticFields

The investigation was set-up to allow the flow of a sucrose solution topass through a magnetic field up to 8 times. An aliquot of solution wasremoved after each pass and allowed to crystallize normally undercontrolled temperature conditions at 50° C. The general visualdifferences in the sucrose crystals formed were similar to thoseobserved under static conditions.

In summary, DC electromagnetic fields promote euhydral growth (i.e. morerectangular form) and appear to slow crystal growth while increasing thenumber of centers of growth (i.e. nucleation) with increasing fieldstrength. Permanent magnetic fields appear to reduce the number ofcenters of growth with increasing field strength and the resultingcrystals are more crystalline compared to the control “no-field”situation.

Differential Scanning Calorimetry (DSC) measurements show the samemelting profile as the static sucrose samples confirming the formationof sucrose hydrates.

3. Preliminary Studies on the Static crystallization of Lactose

Crystallization of lactose was investigated under static conditions inthe presence and absence of magnetic fields. Early observations suggestthat the crystal forms are altered by the magnetic fields. The crystalsformed under the influence of a magnetic field are white in appearanceand have surface texture as compared to the clear, glassy white surfaceobserved in the control (“no-field”) crystals.

4. Further Studies on the Crystallization of Lactose

4.0 Experimental

A 20% undersaturated solution of α-lactose monohydrate (340.00 g, 0.944moles) was prepared and stored in an incubator at 50° C. deionized waterwas used for preparation of the solution and the solvent bottle wascovered to prevent contamination from foreign materials. Care was takento keep this stock solution away from any magnetic fields.

In general, 10 ml of the undersaturated lactose solution was evaporatedin Petri dishes without lids at 50° C. in an incubator. At the bottom ofthe incubator, a tray of silica gel was used to absorb any excessmoisture ensuring that crystallization was not affected by the humidityof the atmosphere in the incubator.

The Petri dishes containing lactose solution were subjected to variousmagnetic fields with differing strengths are described in more detailhereinafter.

4.1 Controlled Environment Studies

A stock solution of α-lactose monohydrate was accurately prepared andstored in an incubator at 50° C. A series of nine experiments werecarried out on the solution, each repeated three times.

4.1.1 Control

A pipette was used to place lactose solution (10 ml) into a Petri dish(5 cm diameter) with the lid in place until placed in the incubator. Thesolution was kept at 50° C. in the incubator until the following daywhen crystallization was complete.

4.1.2 Weakest Permanent Field at Sides in Parallel

Permanent magnetic fields were placed in a wooden base in parallel. The5 cm diameter Petri dish containing the lactose solution (10 ml) wasplaced in the center between the magnets on another empty Petri dish (asa raised platform). The field strengths were measured being about 300 Gat the edges and about 265 G at the center. The solution was keptovernight to crystallize.

4.1.3 Medium Permanent Field at Sides in Parallel

Permanent magnetic fields were placed in a wooden base in parallel withtwo more placed on either side on the outside. The 5 cm diameter Petridish containing the lactose solution (10 ml) was placed in the centerbetween the magnets on another empty Petri dish (as a raised platform).The field strengths were measured being about 640 G at the edges andabout 540 G at the center. The solution was kept overnight tocrystallize.

4.1.4 Strongest Permanent Field at Sides in Parallel

An additional two magnets were placed around those in Experiment 3,making the field strengths about 760 G at the edge and about 630 G atthe center. The 5 cm diameter Petri dish containing 10 ml of a lactosesolution 18 was placed in the center between the magnets on anotherempty Petri dish (as a raised platform). The solution was kept overnightto crystallize. The arrangement used in Experiments 2 to 4 is showndiagrammatically in FIG. 20, numeral 22 shows the general placement ofthe magnet or groups of magnets.

4.1.5 Permanent Field in Parallel Above and Below

The wooden block containing the strongest permanent field set-up wasturned on its side and Petri dish 23 with the lactose solution (10 ml)24 was placed centrally between the parallel magnets on a raisedplatform. The field strengths were measured at about 630 G throughoutthe sample. The solution was then left overnight to crystallize. Thearrangement used is shown diagrammatically in FIG. 21.

4.1.6 Pulsed Field

A hydroflow pulsed magnet 17 was placed on its side with a Petri dishcontaining lactose solution (10 ml) 18 balanced on top. The solution wasthen left overnight to crystallize. The arrangement used is showndiagrammatically in FIG. 22.

4.1.7 Strongest DC Electromagnetic Field

As shown in FIG. 23, a DC electromagnet 19 was placed inside theincubator with the connectors and tubing pulled out through the sidehole of the incubator. A water flow system was set up to ensure that theDC magnet did not overheat. The field strength of the electromagnet wasmeasured to be 600 to 220 Gauss and the Petri dish containing thelactose solution (10 ml) 20 was placed on a raised platform 21 betweenthe two poles of the magnet. The solution was left overnight tocrystallize.

4.1.8 Weakest DC Electromagnetic Field

The field strength of the electromagnet was measured to be 50 to 100Gauss and the Petri dish containing the lactose solution (10 ml) wasplaced on a raised platform between the two poles of the magnet. Thesolution was left overnight to crystallize.

4.1.9 Medium DC Electromagnetic Field

The field strength of the electromagnet was measured to be 160 to 420Gauss and the Petri dish containing the lactose solution (10 ml) wasplaced on a raised platform between the two poles of the magnet. Thesolution was left overnight to crystallize. The arrangement used inExperiments 7 to 9 is shown diagrammatically in FIG. 23.

4.2 Results and Discussion

4.2.0 Introduction

The purpose of the studies was to investigate the effects of appliedfields on the crystallization of lactose under static conditions with aregulated temperature and humidity environment. A 20% undersaturatedsolution was used to ensure that crystallization did not occur tooquickly allowing the effect of the applied fields on the lactosesolution to be at an optimum level.

Five methods were used to investigate the morphology, size andproperties of the lactose solutions crystallized under the influence ofthe applied field these being as follows:

1. Visual observation

2. Differential scanning calorimetry

3. Powder X-ray diffraction

4. Scanning electron microscopy

5. Karl Fischer titrations.

The lactose crystals were removed from the Petri dishes and visualobservations were made noting any changes in brittleness or firmness andplaced in a sintered glass Buchner funnel to dry. The crystals were thenstored in sample tubes at room temperature before being subjected to theother four investigations.

4.2.1 Visual Observations

Visual observations made with the naked eye are summarized in Table4.2.1.

Sample Observations of Crystal Morphology 1(1) 1(2) 1(3) Brittle,white-grey in color, indicative of cL-lactose monohydrate. 2(1)2(2)2(3)Quite similar results to those seen in experiment 1, but crystals wereslightly more brittle, again white-grey colored. 3(1)3(2)3(3)White-yellow colored, two different layers seen. The bottom layer wascrystalline and glassy with tiny “gaps” in the macroscopic structure.The top layer had a rough texture. The phase in between the layers wasvery crystalline. 4(1) 4(2) 4(3) Observations similar to those seen inexperiment 3. 5(1) 5(2) 5(3) Similar to experiments 3 and 4,′ thecrystals were thin and crusty at the edges with an uneven upper surface.Again tiny spaces/gaps were observed, especially on the bottom layer.Crystals were more brittle than those seen in experiment 4. 6(1) 6(2)6(3) Observations were similar to those seen in experiment 5. 7(1) 7(2)7(3) Similar observations to those seen in experiment 5, however thecrystals were more brittle, fine and powdery and very difficult toremove from the Petri dish. 8(1) 8(2) 8(3) Observations were similar tothose seen in experiment 7. 9(1) 9(2) 9(3) Observations were similar tothose seen in experiment 8.

The first notable observation was the color change. The controlsappeared to be glassy-grey whilst the samples crystallized under theinfluence of an applied field had a more “whiter” appearance. Thesamples subject to a permanent field, parallel at sides (experiments2(1) to 4(3)) were visually quite similar to the controls except for theslight color change and the increase in brittleness. Experimentsconducted using a permanent magnet above and below (experiments 5(1) to5(3)) and a hydroflow pulsed magnet (experiments 6(1) to 6(3)) producedyet more brittle crystals with a rougher texture. The DC electromagneticfield (experiments 7(1) to 9(3)) resulted in a very brittle and powderycrystal.

The results suggest that crystallinity of α-lactose monohydrate isimproved and that there are more well formed discrete crystals and lessamorphous glassy lactose. The improved level of brittleness couldpossibly be attributed to a more ordered structure which consequentlyleads to a better cleavage of the crystal in addition to less amorphousglassy lumps within the crystal.

4.2.2 Differential Scanning Calorimetry (DSC)

DSC gives a thermal analysis of the lactose crystals by controlledheating resulting in a melting profile. The results are shown in thefollowing Table where melting temperature in ° C. is stated for each ofthe three samples for each experiment.

TABLE 4.2.2 Expt Sample 1 Sample 2 Sample 3 1 150.9 142.6, 152.0 139.7,150.5 2 141.3, 150.8 143.2, 152.9 143.3, 150.7 3 142.0, 150.0 143.0,151.7 145.0, 219.7 4 143.0, 150.5 142.7, 151.5 144.5, 150.2 5 148.2.151.8 145.0, 150.6 141.2, 150.4 6 144.9, 218.2 143.0, 150.0 143.4, 219.27 143.0, 149.9 142.9, 216.5 143.4, 219.2 8 148.5, 221.2 143.8, 150.8,198.0 142.2, 149.7 9 143.2, 148.6 141.2, 149.1 142.1, 217.7

Results from the literature show that α-lactose monohydrate has amelting temperature at about 143° C. and about 147° C. and about 209° C.where decomposition occurs simultaneously with melting and β-lactose hasa melting temperature at about 236° C. Most of the experimental resultsobtained correspond to the melting temperature of α-lactose whilst a fewsamples produced a higher melting peak at about 219° C. which isindicative of β-lactose. More particularly, most of the experimentsshowed two melting peaks, one at about 142° C. and the other at about152° C., indicative of α-lactose. Some of the samples subject to mediumpermanent field (experiment 3(3)), pulsed field (experiments 6(1) and6(3)) and DC field (experiments 7(2), 7(3), 8(1), 8(2) and 9(3)) showeda higher melting point at about 219° C. in addition to a melting pointat about 140° C. which indicates the presence of β-lactose within thecrystal.

These observations can be explained by the mutarotation properties oflactose and more particularly the fact that α-lactose monohydratemutarotates to form β-lactose until an equilibrium is set up where thereis a higher concentration of β-lactose. The sample shows that in somecases β-lactose is crystallized with the α-lactose, since the highermelting points of about 219° C. are measured.

4.2.3 X-Ray Diffraction (XRD)

The characteristic d-spacings of different lactose crystal forms areshown in the following table:

TABLE 4.2.3 Lactose Structure Characteristic d-Spacing (A) α-Lactosemonohydrate 4.43, 4.64, 5.39 β-Lactose anhydride 4.24, 4.63, 8.41Unstable α-lactose anhydride 4.13, 4.63, 4.93 Stable α-lactose anhydride3.82, 4.21, 4.56 a-Lactose + β-lactose (5:3) 4.04, 4.42, 4.65

Detailed XRD data are not shown but the patterns produced were mostlikely to be α-lactose monohydrate where the characteristic peaksmatched those observed. Characteristic peaks from other lactosestructures did not correlate well with observed patterns and thiseliminates possibilities that the structure of the crystals found couldbe of the β-form, α-anhydride or a mixture of both isomers.

Accordingly, with reference to standard crystal forms it could beconcluded that all samples appeared to be α-lactose monohydrate.

However, the results did not correlate exactly with literature valueswhere d-spacing values seemed to be either slightly larger or smallerthan expected. For example, for experiment 1(1) a d-spacing of 6.91Arather than 7.08A was obtained and for experiment 1(2) a value of 7.23A(again rather than 7.08A) was seen. Other examples were experiment 3(1)where a value of 5.37A was obtained rather than 5.41A and experiment4(2) where 5.51A was seen rather than the literature value of 5.41A. Itshould be noted that these variations were seen only for values aroundthe region of 7.08A and 5.41A whereas other results seem to correlatewell with the literature values.

The variation in d-spacing could indicate a change in interplanarspacing due to water incorporation into the lactose crystal although inthis case the d-spacing would be expected to be consistently larger inall cases rather than fluctuating around the actual value. Thepossibility of inaccuracy in the powder XRD equipment cannot be ruledout.

4.2.4 Scanning Electron Microscopy (SEM) The lactose solutioncrystallized at two different interfaces, these being:

solution/glass where the lactose solution was in contact with the Petridish

solution/air where the lactose solution was in contact with the air andis generally amorphous.

These regions were examined as was a third region:

crystals of solution where the lactose solution crystallized in betweenthe two interfaces. Individual SEMs are not shown.

4.2.4.1 Solution/Glass Interface

In all cases where crystallization had occurred in a magnetic field thesolution/glass interface had less amorphous material and was moredefined and angular compared to the controls.

Experiment 1 consisted of flaky layers of chunky crystals where thesurface appeared to be quite textured. Experiment 2: showed crystals tobe longer, flatter and more crystalline than those seen in experiment 1,growing in the direction of the field lines. The crystals seen inexperiment 4 were well defined with angular shapes and had a reductionin the amorphous material surrounding them compared to the controls.Experiment 5 produced “chunky” crystals with large flat surfaces and thegrowth appeared to be almost layered. More defined, discrete, flat,angular shaped crystals were seen in experiment 7 and in addition moreflaky layers and less amorphous material was seen when compared to thecontrols. Experiments 8 and 9 showed similar, results to those seen inexperiment 7.

4.2.4.2 Solution/Air Interface

The solution/air interface shows more crystalline, fibrous material inall magnetic fields compared to the control which is almost amorphouswith crystalline regions.

Experiment 1 showed the amorphous material to have some form in theshape of fans. Less amorphous material was seen in experiment 2,indicated by more crystalline regions on the surface. Experiment 6produced long, fibre-like formation on the surface and compared to thecontrol the samples had definite texture and well formed fibrouscrystals. Ordered chunks on the surface pointing in a similar directionon an elongated axis were observed in experiment 7 and the surface wasnot amorphous like the controls. Experiment 8 showed crystals havinglong fan like projections and appearing to be fibrous. Non-amorphous butneedle-like or fibrous crystals were seen in experiment 9.

4.2.4.3 Crystals of Solution

Elongated, plate-like crystals were observed in the solution crystals inall magnetic field samples, particularly with DC fields. Experiment 1showed crystals having a regular, cuboid shape with flat surfaces andangled corners, coated with amorphous material. Experiment 2 producedcrystals less defined than the controls having rounded corners coveredwith amorphous material. Well defined and angular shapes withpredominating layers were seen in experiment 4 and there also appearedto be less amorphous material than seen in the controls. Experiment 6showed crystals to be better formed with flatter and more angledsurfaces than those seen in the controls. Experiment 7 produced crystalsthat were longer and more layered with less amorphous material then thecontrols. Experiments 8 and 9 showed layer formation again withelongated and well formed crystals.

Generally a more defined crystal with less amorphous coating wasproduced when solutions were crystallized under the influence of amagnetic field. In addition very prominent layer formation of elongatedcrystals was observed in the samples crystallized under applied fieldscompared to the more random formation of crystals seen in the controlexperiments.

4.2.5 Karl Fischer Titrations (KF)

The expected moisture content of α-lactose monohydrate is 4.9997%. Eachsample was titrated three times and the mean wt/wt and standarddeviations recorded. Data for individual samples are not shown.

Experiment 1 (control) showed mean values from 5.34% to 5.42% with astandard deviation of ±0.10%. If the mean wt/wt percentages (consideringstandard deviation) were within this range then the results for moisturecontent would not be regarded as significantly different. A general ruleof thumb is to extend the limits to two standard deviations.

Results from the titrations show that samples crystallized in DC fieldshave an increase in moisture content of around 7.5 to 11% wt/wt comparedto the controls and permanent fields (above and below) show an increasein moisture content of about 7% wt/wt. Other samples did not have asignificantly higher moisture content.

In addition to the measurement of additional water within the lactosemolecule, these results confirm the powder XRD results that thea-monohydrate crystal form is obtained in all cases.

4.2.6 Conclusions

It is clear that magnetic fields affect the crystallization of lactoseand a summary of all the results is shown in the following Table 4.2.6.Powder XRD and KF titrations show that the crystal form is not alteredby applied fields and remains the α-lactose monohydrate. Crystallinityof the lactose crystal increased, i.e. a well formed, more brittle andpowdery crystal was produced when the lactose solution was subject tomagnetic fields during crystallization. SEM results showed the formationof layers and different morphology where crystals were seen to be moreelongated and regular rather than being uneven blocks as seen incontrols. The amorphous content of the crystals was seen to decreasewhen a magnetic field was applied. Karl Fischer titrations indicateadditional water in the lactose crystal when subject to magnetic fields.The water may be strongly bound in the crystal lattice or weakly boundas water inclusions. Powder XRD did not rule out any of thesepossibilities.

TABLE 4.2.6 DSC (° C.) XRD SEM Icy 1(1) 150.9 α-l'ose m'hydSolution/glass-chunky 5.395 1(2) 142.6,152.0 α-1'ose m'hyd Crystals withflaky layers 1(3) 139.7,150.5 α-l'ose m'hyd Solution/air-amorphoussurface some form in the shape of fans Crystals of solution-regular,flat surfaces with angled corners with amorphous coating 2(1)141.3,150.8 α-l'ose m'hyd Solution/glass-longer crys- 5.411 2(2)143.2,152.9 α-l'ose m'hyd tals seen Solution/air-less 2(3) 143.3,150.7α-lose m'hyd amorphous material on the surface compared to controlsCrystals of solution-crystals have less form than controls 3(1)142.0,150.0 α-l'ose m'hyd Solution/glass-discrete, 5.674 3(2)143.0,151.7 α-l'ose m'hyd well-formed crystals with 3(3) 145.0,219.7α-l'ose m'hyd amorphous material be- tween Solution/air-similar to 2 (2)Crystals of solution-well defined crystals with some amorphous material4(1) 143.0,150.5 α-l'ose m'hyd Solution/glass well-formed 5.532 4(2)142.7,151.5 α-l'ose m'hyd angular crystals with 4(3) 144.5,150.2 α-l'osem'hyd significantly less amor- phous material Solution/ air-similar to 2(2) Crystals of solution-well formed, with angular shapes, withpredominating layers 5(1) 148.2,151.8 α-l'ose m'hyd Solution/glass-analmost 5.758 5(2) 145.0,150.6 α-l'ose m'hyd layered growth Solution/air-5(3) 141.2,150.4 α-l'ose m'hyd some amorphous material on the surfaceCrystals of solution-well formed crystals with some amorphous material6(1) 144.9,218.2 α-l'ose m'hyd Solution/glass-regular 5.634 6(2)143.0,150.0 α-l'ose m'hyd formed, angular crystals 6(3) 143.4,219.2α-l'ose m'hyd with flat surfaces Solution/ air-very fibrous surface seenCrystals of solution-well formed, flat, angled sur- faces, with somelayers 7(1) 143.0,149.9 α-l'ose m'hyd Solution/glass-discrete, 5.8137(2) 142.9,216.5 α-l'ose m'hyd well formed crystals with 7(3)143.4,219.2 α-l'ose m'hyd flaky layers of material Solution/air-orderedchunks, with growth in one direction on an elongated axis - notamorphous Crystals of solution-very layered, with elongated shapes,little amorphous 8(1) 148.5,211.2 α-l'ose m'hyd Solution/glass-wellformed, 5.868 8(2) 143.8,150.8 α-l'ose m'hyd flat, angular crystals -198.0 very little amorphous 8(3) 142.2, 149.7 α-l'ose m'hyd materialSolution/air-fibrous, fan- like projections - no longer amorphousCrystals of solution-well formed, discrete, layered crystal 9(1)143.2,148.6 α-l'ose m'hyd Solution/glass-well formed, 6.092 9(2)141.2,149.1 α-l'ose m'hyd angular crystals with little 9(3) 142.1,217.7α-l'ose m'hyd amorphous material Solution/air-crystalline, needle-likelayers seen - not amorphous Crystals of solution- elongated, welldefined crystals with layer formation KF = Karl Fischer titration (%wt/wt) α-l'ose m'hyd = α-lactose monohydrate

5. Production of Milk Chocolate

The following (headed “Old Recipe”) is a recipe for milk chocolate basedon Jackson in “Industrial Chocolate Manufacture and Use”, Blackies,1988, page 254, Table 13.5 together with a modified recipe (headed “WithSucrose Hydrate”) to take account of the use of sucrose hydratecontaining 10% water:

Percentage Composition Old Recipe With Sucrose Hydrate Cocoa Mass 1211.4 Milk Powder 14 13.3 Sugar 52.25 49.8 Add Cocoa Butter 21.35 20.3Lecithin 0.3 0.3 Water in Hydrate 5.0 Calories/g (calculated) 5.5 5.2

The chocolate can be manufactured using conventional methods, forexample as set out in the reference mentioned above. The figures forcalories/gram are calculated on the basis of fat=9 cal/g, carbohydrateand protein=4 cal/g and assuming about 2.5% fibre.

What is claimed is:
 1. A process for preparing crystalline sugar, theprocess comprising: providing a solution comprising about 20 to 40%sugar and about 80 to 60% solvent based on the total weight of thesolution; exposing the solution to a magnetic field having a strength ofbetween about 30 and 760 G which magnetic field strength is sufficientto influence at least one of morphology, size, nucleation rate, orcrystallinity of the resulting crystalline sugar product; and providingconditions suitable for crystallization to obtain a substantiallycrystalline sugar product with fewer centers of nucleation.
 2. Theprocess of claim 1 wherein the sugar is sucrose, glucose, fructose,lactose, trehalose, sorbitol, mannitol, erythritol, or a combinationthereof.
 3. The process of claim 1 wherein the solvent is water and thecrystalline sugar product comprises sucrose hydrate.
 4. The process ofclaim 1 wherein the crystalline sugar product comprises at least about1% water by weight.
 5. The process of claim 1 wherein the solvent iswater, the solution is from about 10 to 30% unsaturated, and themagnetic field is applied when no seed crystals are present.
 6. Theprocess of claim 5 wherein the solution comprises from about 20 to 40%sucrose and about 80 to 60% water based on the total weight of thesolution and the temperature during at least a portion of thecrystallization is from about 35 to 65° C.
 7. The process of claim 1wherein the sugar consists essentially of lactose and the solvent iswater.
 8. The process of claim 1 wherein at least a portion of thesolution is exposed to a magnetic field from at least one DCelectromagnet during the exposing step, the magnet providing a magneticfield strength of at least about 50 to 600 G.
 9. The process of claim 1wherein the magnetic field is applied using at least one pulsed magnet.10. The process of claim 1 which further comprises maintaining at leasta portion of the solution at a temperature of from about 30 to about 70°C. during at least a portion of the crystallization step.
 11. A processof preparing a food or confectionery product which comprises preparing asubstantially crystalline product according to claim 1 and utilizing thesubstantially crystalline sugar product as an ingredient in or a coatingon the food or confectionery product.
 12. A crystalline sugar productprepared by the process of claim 1 and having a water content of atleast 1% by weight.
 13. The crystalline sugar product of claim 12 in theform of sucrose hydrate optionally in combination with anhydroussucrose.
 14. The crystalline sugar product of claim 12 in the form ofcrystalline lactose.
 15. A food or confectionary product prepared withthe crystalline sugar product of claim
 12. 16. The food or confectionaryproduct of claim 15 further comprising chocolate.
 17. The food orconfectionary product of claim 15 wherein the crystalline sugar productis present in the form of a coating.
 18. The process of claim 1, whereinat least a portion of the solution is exposed to the magnetic fieldwhile evaporating an amount of solvent sufficient to causecrystallization of the sugar.